Degradable soft cotton towel and preparation method thereof

Abstract

The application discloses a degradable cotton soft towel and a preparation method thereof, relates to the technical field of fiber composite materials, and belongs to the patent classification D01F8 / 02. The preparation method comprises the following steps: performing alkali treatment and enzymolysis on Egyptian long-staple cotton fibers to obtain pretreated cotton fibers, and preheating, stretching and setting poly-caprolactone fibers to obtain pretreated poly-caprolactone fibers; mixing and opening the two kinds of fibers, and then air-laying to form a fiber web; constructing a super water-absorbing network by impregnating a main network solution carboxymethyl chitin and oxidized cellulose nanofilament and an auxiliary network dispersion liquid calcium alginate gel microspheres and a hyaluronic acid crosslinking body; forming micron protrusions through hexagonal nickel template hot pressing, and obtaining a base by electrostatic spraying modification of nano silicon dioxide; and obtaining the cotton soft towel through vacuum drying, slitting and sterilization after spraying of an essence liquid. The cotton soft towel has excellent water absorption performance through the synergistic effect of multistage pores, a super water-absorbing network and micro-nano surface modification, and the poly-caprolactone fibers and the cotton fibers used in the cotton soft towel are mixed, and both have good biodegradability.

Description

Technical Field

[0001] This invention relates to the field of fiber composite materials technology, belonging to patent classification number D01F8 / 02, specifically to a biodegradable cotton towel and its preparation method. Background Technology

[0002] Cotton wipes, as a new type of cleaning and skincare product with a soft touch and a pleasant user experience, have seen increasingly widespread application in personal care, daily cleaning, and medical care consumables in recent years. With their delicate, skin-friendly, and lint-free properties, they provide gentle cleansing and care for the skin, making them especially suitable for babies, those with sensitive skin, and others who have high demands for skin feel. At the same time, cotton wipes offer flexibility for both dry and wet use, meeting the needs of various scenarios such as makeup removal, facial cleansing, and daily wiping, gradually becoming an upgraded alternative to traditional tissues and cotton pads, and are widely favored by consumers.

[0003] With increasing environmental awareness and the growing acceptance of sustainable development concepts, consumers are demanding higher biodegradability from cotton wipes. Currently, some cotton wipes on the market use a blend of cotton and other hydrophilic fibers to achieve good absorbency. However, these hydrophilic fibers are mostly non-biodegradable materials, such as polyester and viscose fibers, which are chemically synthesized fibers. Polyester fibers are made from organic diacids and diols through chemical polycondensation, while viscose fibers are made from wood pulp and other raw materials through chemical processing.

[0004] The widespread use of these non-degradable fibers has brought about serious environmental problems. With the rapid increase in the use of cotton towels, discarded cotton towels are extremely difficult to degrade in the natural environment. Long-term accumulation not only occupies a large amount of land resources, but also damages soil structure and ecosystems, affects the living environment of animals and plants, forms "white pollution," and places a heavy burden on the environment. Summary of the Invention

[0005] The purpose of this invention is to provide a biodegradable cotton towel and its preparation method, thereby solving the technical problems mentioned in the background section. The cotton towel prepared by this invention not only has good biodegradability but also excellent water absorption properties, thus meeting the needs of daily skin hygiene care.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A method for preparing a biodegradable cotton towel includes the following steps:

[0008] a) taking Egyptian long-staple cotton fibers as raw materials, first placing them in a sodium hydroxide aqueous solution for alkali treatment, and then repeatedly washing them with deionized water until neutral; then immersing the cotton fibers in a cellulase solution prepared by using an acetic acid buffer solution to perform enzymatic hydrolysis, and after the enzymatic hydrolysis is completed, heating and inactivating to obtain pretreated cotton fibers;

[0009] b) taking polycaprolactone fibers as raw materials, placing them in a hot air oven for preheating, then performing stretching at a constant stretching rate, and then immediately cooling and setting to obtain pretreated polycaprolactone fibers;

[0010] c) mixing the pretreated cotton fibers and the pretreated polycaprolactone fibers, opening them with a needle cloth opener, and then forming a fiber web using an air-laid machine;

[0011] d) first preparing a main network solution obtained by dissolving carboxymethyl chitin and oxidized cellulose nanofilament in deionized water; then preparing an auxiliary network dispersion liquid obtained by dispersing calcium alginate gel microspheres and hyaluronic acid crosslinked bodies in deionized water and ultrasonic treatment; immersing the fiber web obtained in step c) in the auxiliary network solution, then removing the liquid with a roller and drying, and then immersing it in the main network solution, removing the liquid with a roller and drying, so as to build a superabsorbent network inside the fiber web, thereby obtaining an absorbent fiber web;

[0012] e) selecting a nickel template with a hexagonal protrusion array, placing the fiber web in a hot press for pressing, then naturally cooling and demolding, forming a micron-level protruding structure on the surface, then preparing a nano-silicon dioxide ethanol suspension, uniformly spraying it on the surface of the absorbent fiber web using an electrostatic spraying device, and then drying to obtain a cotton-soft towel base;

[0013] f) spraying the essence liquid on the cotton-soft towel base, then vacuum drying, and finally cutting and irradiation sterilization, thereby obtaining the product.

[0014] In this invention, Egyptian long-staple cotton fibers undergo a graded treatment to form a unique porous structure. This multi-scale porous system significantly improves wettability through physical structure optimization. The alkali treatment selectively dissolves the waxy layer and primary cell walls on the fiber surface, exposing cellulose microfiber bundles and forming micron-scale groove structures. These grooves provide channels for rapid liquid diffusion. Subsequent enzymatic hydrolysis further etches a nanoscale pore network within the micron-scale grooves, significantly increasing the fiber's specific surface area and surface active sites. The internal microchannels formed by the stretching of polycaprolactone fibers complement the surface structure of the cotton fibers, constructing a four-level continuous pore network consisting of interfiber gaps, internal interfiber gaps, surface microgrooves, and nanopores. This multi-level pore structure generates a gradient capillary effect, allowing liquid to spontaneously and rapidly permeate along the pores from macropores to micropores. Simultaneously, the strong capillary force generated by the nanoscale pores ensures the uniform distribution and stable retention of the liquid within the material. Secondly, in the construction of the superabsorbent network of the biodegradable superabsorbent cotton towel, the main absorbent network and the auxiliary absorbent network achieve efficient water absorption, rapid water transfer, and stable water retention through complementary material properties and structural synergy. The main absorbent network is formed by dissolving carboxymethyl chitin and oxidized cellulose nanofibers in deionized water. Carboxymethyl chitin contains a large number of hydrophilic carboxyl and hydroxyl groups, which have good water solubility and film-forming properties. Oxidized cellulose nanofibers form a three-dimensional network due to their high specific surface area and abundant hydroxyl groups. The viscous solution formed by the two adheres to the surface of the fiber network after impregnation, constructing a continuous hydrophilic film, enhancing the affinity of the fiber network for liquid, and filling the gaps between fibers to form a continuous transport channel from the surface to the interior, laying the foundation for rapid liquid penetration and diffusion. The auxiliary water-absorbing network is formed by ultrasonic dispersion of calcium alginate gel microspheres and hyaluronic acid cross-linked polymers. The three-dimensional network structure inside the calcium alginate gel microspheres can lock in water molecules through osmosis, while the hyaluronic acid cross-linked polymers reduce water loss in a water-rich gel form. Ultrasonic treatment breaks up the aggregation of the two, making them uniformly dispersed and forming a composite structure of "main framework-dispersed water storage unit". The calcium alginate microspheres provide independent water storage space to avoid back osmosis, while the hyaluronic acid cross-linked polymers fill the gaps and enhance water retention capacity. The synergistic nature of the two is the complementary function of "rapid transport" and "efficient water storage". The continuous channels of the main network ensure that the liquid quickly penetrates to each area, and the auxiliary network water storage unit quickly absorbs and stores the liquid after it arrives. The dispersed microspheres and cross-linked polymers do not block the channels and can also reduce pore size through swelling, thereby enhancing capillary pressure and improving transport efficiency. This "framework-storage" structure solves the contradiction between water absorption and water retention of a single material, and all materials used are natural and biodegradable, ensuring environmental sustainability while improving performance. Finally, by constructing micron-scale and nano-scale silica protrusion structures on the fiber surface, the combination of these two structures forms a micro / nano protrusion structure that significantly improves the surface roughness of the fiber, increases the hydrophilicity of the fiber web surface, and enhances the conduction of water from the surface to the interior. For example... Figure 1The SEM image of the surface of the cotton soft towel base body of the present application can be observed from the electron microscope image, and the fiber web surface presents a rough structure with unevenness. The present application has excellent water absorption performance through the synergistic effect. In addition, the cotton fiber and polycaprolactone fiber used in the present application have good degradability and do not cause environmental pollution, which is green and environmentally friendly.

[0015] Preferably, in step a), the concentration of sodium hydroxide solution is 2-5 wt%, the alkali treatment temperature is 50-60 DEG C, and the alkali treatment time is 10-20 min.

[0016] Preferably, in step b), the preheating temperature of polycaprolactone fiber is 85-90 DEG C, the preheating time is 5-10 min, and the stretching multiple is 2-3 times.

[0017] Preferably, in step c), the mass ratio of pretreated cotton fiber to pretreated polycaprolactone fiber is 10:3-7.

[0018] Preferably, in step d), the mass ratio of carboxymethyl chitin to oxidized cellulose nanofiber is 5:2-4.

[0019] Preferably, in step d), the mass ratio of calcium alginate gel microspheres to hyaluronic acid crosslinker is 10:4-6.

[0020] Preferably, the preparation method of the hyaluronic acid crosslinker comprises the following steps:

[0021] The hyaluronic acid powder is added to deionized water, stirred and dissolved, then sodium hydroxide solution is added to adjust the pH to 8.5-9.0, then 1,4-butanediol diglycidyl ether is added, heated and stirred to react, washed and freeze-dried to obtain the hyaluronic acid crosslinker.

[0022] Preferably, in step e), the modified nano-silicon dioxide comprises the following steps:

[0023] The nano-silicon dioxide is added to a mixed solvent of ethanol and water, ultrasonically oscillated and uniformly dispersed, then gamma-glycidyl ether oxypropyl trimethoxysilane is added, the pH is adjusted to 4-5, heated and stirred to react, centrifuged, washed and dried to obtain the epoxidized nano-silicon dioxide.

[0024] The dodecyl dimethyl aminopropyl ammonium chloride is added to deionized water, stirred and dissolved, then the epoxidized nano-silicon dioxide is added, heated and stirred to react, centrifuged, washed and dried.

[0025] Preferably, in step f), the essence liquid comprises the following components by weight:

[0026] Peach gum polysaccharide 5-10 parts, collagen 2-5 parts, sodium hyaluronate 1-3 parts, glycerol 1-3 parts, deionized water 80-90 parts.

[0027] In the technical scheme of the present application, as described above, the nanometer silicon dioxide is combined on the surface of the fiber web to improve the roughness of the surface of the fiber web, and further improve the hydrophilicity of the surface of the fiber web. However, the present application team further encountered a problem in the experiment that a large amount of nanometer silicon dioxide fell off from the surface of the fiber web in the subsequent drying process, affecting the improvement of the hydrophilicity of the surface of the fiber web. In order to further solve this problem, the nanometer silicon dioxide is modified in the present application. First, gamma-glycidoxypropyltrimethoxysilane is grafted on the nanometer silicon dioxide to load epoxy functional groups on the surface of the nanometer silicon dioxide. Then, ring-opening reaction occurs between the epoxy functional groups and the amino groups on the dodecyl dimethyl amino propyl ammonium chloride, so that the dodecyl dimethyl amino propyl ammonium chloride is grafted on the surface of the nanometer silicon dioxide, and the surface of the silicon dioxide is positively charged. The fiber web is negatively charged under the action of carboxymethyl chitin and oxidized cellulose nanofibril. Under the action of electrostatic force, the nanometer silicon dioxide can be firmly combined on the surface of the fiber web, so that a clear micro-nano composite structure is formed on the surface of the fiber web, the roughness of the fiber surface is improved, and the hydrophilicity of the surface is further improved.

[0028] A degradable cotton soft towel is prepared by the method described above.

[0029] Compared with the prior art, the present application has the following beneficial effects:

[0030] 1. The gradient capillary effect is generated by the multi-level pore structure design (four-level continuous pore network of fiber gap, internal gap, surface micro-groove and nano-pore), and the synergistic effect of the main water absorption network (continuous hydrophilic transmission channel constructed by carboxymethyl chitin and oxidized cellulose nanofibril) and the auxiliary water absorption network (water storage structure of "skeleton-reservoir" formed by calcium alginate gel microspheres and hyaluronic acid crosslinking body) greatly improves the water absorption speed, water absorption capacity and water retention stability of the cotton soft towel, and the surface micro-nano convex structure enhances the hydrophilicity, meeting the needs of efficient water absorption in daily cleaning and medical nursing consumables, and improving the poor water absorption performance of traditional degradable cotton soft towels.

[0031] 2. Natural degradable Egyptian long-staple cotton fibers and polycaprolactone fibers are used as base materials, and natural degradable materials are selected for the water absorption network and the essence liquid components. The performance is improved by physical modification (hot stamping, electrostatic spraying, etc.) and structure optimization, without sacrificing the degradable characteristics of the materials, solving the contradiction between high water absorption and environmental protection in traditional technologies, reducing the pollution to the environment after use, and meeting the green consumption trend. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1SEM image of the surface of the base body of the soft cotton towel according to the present application. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present application will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0034] Embodiment 1

[0035] A preparation method of a degradable soft cotton towel, comprising the following steps:

[0036] Step a: 500 g of Egyptian long-staple cotton fibers are weighed and placed in a 5000 mL aqueous sodium hydroxide solution with a concentration of 3 wt%, and stirred at 55°C in a constant temperature water bath for 15 minutes (stirring rate 200 rpm). After the treatment is completed, the fibers are repeatedly rinsed with deionized water until the pH value of the washing liquid reaches 7.0±0.2. The alkali-treated cotton fibers are immersed in a cellulase solution prepared with an acetic acid buffer solution with pH=4.8 (enzyme activity 2000 U / g, mass-volume ratio of fibers to solution 1:10), and subjected to enzymatic hydrolysis in a 45°C shaking water bath (150 rpm) for 30 minutes. Immediately after the enzymatic hydrolysis is completed, the system is warmed to 80°C for 10 minutes to inactivate the enzyme. After filtration, the pretreated cotton fibers are drained and placed in a well-ventilated place for use.

[0037] Step b: 200 g of polycaprolactone fibers (1.5 dtex) are weighed and laid flat in a hot air oven, and preheated at 88°C for 8 minutes. The preheated fibers are fixed on a stretching device, and stretched to 2.8 times the original length at a constant rate of 10 mm / min. Immediately after the stretching is completed, the fibers are blown to room temperature for setting, to obtain pretreated polycaprolactone fibers, which are sealed and stored to avoid moisture.

[0038] Step c: The pretreated cotton fibers and the pretreated polycaprolactone fibers are mixed in a mass ratio of 10:6 (total weight 700 g), and placed in an opener with a needle spacing of 0.5 mm for opening 3 times to ensure uniform mixing of the fibers. The opened mixed fibers are sent to an air-laid machine, and a web with a grammage of 50±2 g / m 2 is prepared by setting the working air pressure to 0.6 MPa, the environmental temperature to 25±1°C, and the relative humidity to 60±5%. The web uniformity variation coefficient is controlled to be ≤8%. Immediately after the web is formed, a pressure roller with a pressure of 0.5 MPa is used for pre-pressing for 30 seconds to enhance the bonding force between the fibers.

[0039] Step d: Preparation of the main network solution: 25 g of carboxymethyl chitin (88% deacetylation) and 18 g of oxidized cellulose nanofibrils (30 nm in diameter) were weighed and added to 460 mL of deionized water. The mixture was stirred at 50°C for 2 hours until completely dissolved, forming a uniform viscous solution.

[0040] Preparation of the auxiliary network dispersion solution: 500 mL of deionized water was added to a beaker, and 5 g of hyaluronic acid powder was weighed and added. A magnetic stirrer was used to stir at a speed of 200 rpm for 30 minutes until the hyaluronic acid was completely dissolved. Then, 1 mol / L sodium hydroxide solution was slowly added, and the pH of the solution was adjusted to 8.5-9.0 using pH paper. 2 g of 1,4-butanediol diglycidyl ether was slowly added to the above solution, and the stirring speed was increased to 300 rpm. The beaker was placed in a constant temperature water bath at 40°C, and the reaction was stirred for 6 hours. After the reaction was completed, the mixture was transferred to a centrifuge tube and centrifuged at 8000 rpm for 15 minutes. The supernatant was discarded, and the precipitate was washed with deionized water three times. After each washing, the precipitate was centrifuged and separated. The washed precipitate was placed in a freeze dryer and pre-frozen at -40°C for 2 hours. Then, it was freeze-dried under a vacuum of ≤10 Pa for 12 hours to obtain a hyaluronic acid cross-linked body.

[0041] Step c: Preparation of the auxiliary network dispersion solution: 500 mL of deionized water was added to a beaker, and 5 g of hyaluronic acid powder was weighed and added. A magnetic stirrer was used to stir at a speed of 200 rpm for 30 minutes until the hyaluronic acid was completely dissolved. Then, 1 mol / L sodium hydroxide solution was slowly added, and the pH of the solution was adjusted to 8.5-9.0 using pH paper. 2 g of 1,4-butanediol diglycidyl ether was slowly added to the above solution, and the stirring speed was increased to 300 rpm. The beaker was placed in a constant temperature water bath at 40°C, and the reaction was stirred for 6 hours. After the reaction was completed, the mixture was transferred to a centrifuge tube and centrifuged at 8000 rpm for 15 minutes. The supernatant was discarded, and the precipitate was washed with deionized water three times. After each washing, the precipitate was centrifuged and separated. The washed precipitate was placed in a freeze dryer and pre-frozen at -40°C for 2 hours. Then, it was freeze-dried under a vacuum of ≤10 Pa for 12 hours to obtain a hyaluronic acid cross-linked body.

[0042] Step e: A nickel template with a height of 30 μm and a pitch of 80 μm was selected, and the water-absorbing fibrous web obtained in step d was laid on the template and placed in a hot press at 70°C and 5 MPa for 5 seconds. After natural cooling, the template was removed, and a micron-level protruding structure was formed on the surface.

[0043] Preparation of modified nano-silica: 5 g of nano-silica was added to 200 mL of ethanol-water mixed solvent (volume ratio 3:1) and ultrasonically dispersed for 30 minutes; 8 g of γ-glycidyloxypropyltrimethoxysilane was added, and the pH was adjusted to 4-5 with glacial acetic acid, and then the mixture was stirred at 60°C for 4 hours. After centrifugal washing and drying, the epoxidized nano-silica was obtained. 3 g of dodecyl dimethyl amino propyl ammonium chloride was dissolved in 150 mL of deionized water, and the epoxidized nano-silica was added. The mixture was stirred at 70°C for 6 hours. After centrifugal washing and drying, the modified nano-silica was obtained.

[0044] The modified nano-silica was prepared into a 0.5 wt% ethanol suspension, and was uniformly sprayed onto the surface of the fiber web using an electrostatic spraying device (voltage 15 kV, flow rate 10 mL / min, nozzle distance from the fiber web 15 cm) (the spraying amount was 10% of the mass of the fiber web). The fiber web was dried in a 60°C oven for 10 minutes to obtain the cotton-soft towel base.

[0045] Step f: 9 parts of peach gum polysaccharide, 4 parts of collagen, 2.5 parts of sodium hyaluronate, and 2.5 parts of glycerol were weighed out, and 88 parts of deionized water was added. The mixture was stirred until completely dissolved to prepare the serum. The serum was uniformly sprayed onto the surface of the cotton-soft towel base obtained in step e using a spraying device (the spraying amount was 15% of the mass of the base). Then, the cotton-soft towel base was placed in a vacuum drying oven and dried at 40°C and -0.09 MPa for 2 hours. The dried material was cut into pieces using a cutting machine and subjected to irradiation sterilization to obtain the degradable cotton-soft towel product.

[0046] Example 2

[0047] A method for preparing a degradable cotton-soft towel, comprising the following steps:

[0048] Step a: 500 g of Egyptian long-staple cotton fibers were weighed out and placed in 5000 mL of 3 wt% sodium hydroxide aqueous solution. The mixture was stirred in a 55°C constant-temperature water bath for 15 minutes (stirring rate 200 rpm). After the treatment was completed, the fibers were repeatedly washed with deionized water until the pH of the washing solution reached 7.0±0.2. The alkali-treated cotton fibers were immersed in a cellulase solution prepared with an acetic acid buffer solution with pH=4.8 (enzyme activity 2000 U / g, mass / volume ratio of fibers to solution 1:10). The mixture was subjected to enzymatic hydrolysis in a 45°C shaking water bath (150 rpm) for 30 minutes. After the enzymatic hydrolysis was completed, the system was immediately heated to 80°C and maintained for 10 minutes to inactivate the enzyme. After filtration, the pretreated cotton fibers were obtained and drained in a well-ventilated place for use.

[0049] Step b: 200 g polycaprolactone fiber (1.5 dtex) was weighed and laid flat in a hot air oven and preheated at 88°C for 8 minutes. The preheated fiber was fixed on a stretching device and stretched to 2.3 times the original length at a constant rate of 10 mm / min. After stretching, the fiber was immediately blown to room temperature for setting with cold air. The pretreated polycaprolactone fiber was sealed and stored to avoid moisture.

[0050] Step c: The pretreated cotton fiber and the pretreated polycaprolactone fiber were mixed in a mass ratio of 10:4 (total weight 700 g), and put into an opener with a needle spacing of 0.5 mm and opened 3 times to ensure uniform mixing of the fibers. The opened mixed fibers were fed into an air laying machine, and the working air pressure was set to 0.6 MPa, the environmental temperature was 25±1°C, and the relative humidity was 60±5%. A web with a grammage of 50±2 g / m 2 was prepared, and the uniformity variation coefficient of the web was controlled to be ≤8%. After webbing, the fibers were pre-pressed with a pressure roller at 0.5 MPa for 30 seconds to enhance the bonding force between the fibers.

[0051] Step d: Preparation of the main network solution: 25 g carboxymethyl chitin (degree of deacetylation 88%) and 12 g oxidized cellulose nanofibril (diameter 30 nm) were weighed and added together into 460 mL deionized water. The mixture was stirred at 50°C for 2 hours until completely dissolved, forming a uniform viscous solution.

[0052] Preparation of the auxiliary network dispersion solution: 500 mL deionized water was added to a beaker, and 5 g hyaluronic acid powder was weighed and added to the beaker. A magnetic stirrer was used to stir at a speed of 200 rpm for 30 minutes until the hyaluronic acid was completely dissolved. Then, 1 mol / L sodium hydroxide solution was slowly added, and the pH of the solution was adjusted to 8.5-9.0 using pH paper. 2 g of 1,4-butanediol diglycidyl ether was slowly added to the above solution, and the stirring speed was increased to 300 rpm. The beaker was placed in a constant temperature water bath at 40°C, and the stirring was continued for 6 hours. After the reaction was completed, the mixture was transferred to a centrifuge tube and centrifuged at a speed of 8000 rpm for 15 minutes. The supernatant was discarded. The precipitate was washed repeatedly with deionized water for 3 times, and centrifugation was performed after each washing. The washed precipitate was placed in a freeze dryer and pre-frozen at -40°C for 2 hours, and then freeze-dried under a vacuum degree of ≤10 Pa for 12 hours to obtain the hyaluronic acid crosslinker.

[0053] Take 20 g of calcium alginate gel microspheres (particle size 30 μm) and 9 g of hyaluronic acid crosslinking body, add 300 mL of deionized water, and use a 40 kHz, 300 W ultrasonic device to treat for 15 minutes until evenly dispersed. The fiber web obtained in step c is first immersed in the auxiliary network dispersion solution at a speed of 2 m / min (immersion time 60 seconds), and then dried in a 60°C hot air dryer for 2 minutes after removing the liquid with a 0.2 MPa roller; then the fiber web is immersed in the main network solution at the same speed (immersion time 30 seconds), and then dried in a 60°C hot air dryer for 3 minutes after removing the liquid with a 0.2 MPa roller, to obtain a water-absorbing fiber web.

[0054] Step e: Select a nickel template with a height of 30 μm and a pitch of 80 μm hexagonal protrusion array, and lay the water-absorbing fiber web obtained in step d on the template, and place it in a hot press at 70°C and 5 MPa for 5 seconds, then cool naturally and demold to form micron-level protruding structures on the surface.

[0055] Preparation of modified nanosilica: Take 5 g of nanosilica and add it to 200 mL of ethanol-water mixed solvent (volume ratio 3:1), and ultrasonically disperse for 30 minutes; add 8 g of γ-glycidoxypropyltrimethoxysilane, adjust the pH to 4-5 with glacial acetic acid, and stir at 60°C for 4 hours. Centrifugal wash and dry to obtain epoxidized nanosilica; take 3 g of dodecyl dimethyl amino propyl ammonium chloride and dissolve it in 150 mL of deionized water, add the epoxidized nanosilica, and stir at 70°C for 6 hours. After centrifugal washing and drying, the modified nanosilica is obtained.

[0056] Prepare a 0.5 wt% ethanol suspension of the modified nanosilica, and use an electrostatic spraying device (voltage 15 kV, flow rate 10 mL / min, nozzle distance from the fiber web 15 cm) to uniformly spray it onto the surface of the fiber web (spraying amount 10% of the mass of the fiber web), and dry it in a 60°C oven for 10 minutes to obtain a soft cotton towel base.

[0057] Step f: Take peach gum polysaccharide 6 parts, collagen 3 parts, sodium hyaluronate 1.5 parts, and glycerol 1.5 parts by weight, add 83 parts of deionized water, and stir until completely dissolved to prepare the essence. The essence is uniformly sprayed onto the surface of the soft cotton towel base obtained in step e by a spraying device (spraying amount 15% of the mass of the base), and then placed in a vacuum drying oven at 40°C and -0.09 MPa for 2 hours. The dried material is cut into pieces by a cutting machine and sterilized by irradiation to obtain the degradable soft cotton towel product.

[0058] Example 3

[0059] A method for preparing a degradable soft cotton towel, comprising the following steps:

[0060] Step a: Take 500 g of Egyptian long-staple cotton fibers and place them in a 5000 mL aqueous sodium hydroxide solution with a concentration of 3 wt%. Stir the mixture in a constant temperature water bath at 55°C for 15 minutes (stirring rate 200 rpm). After the treatment is complete, rinse the fibers repeatedly with deionized water until the pH of the washing solution reaches 7.0±0.2. Soak the alkali-treated cotton fibers in a cellulase solution prepared with an acetic acid buffer solution at pH=4.8 (enzyme activity 2000 U / g, fiber-to-solution mass-to-volume ratio 1:10) in a 45°C shaking water bath (150 rpm) for 30 minutes. Immediately after the enzymatic hydrolysis is complete, raise the temperature of the system to 80°C for 10 minutes to inactivate the enzyme. After filtration, obtain the pretreated cotton fibers and let them drain in a well-ventilated area for later use.

[0061] Step b: Take 200 g of polycaprolactone fibers (1.5 dtex) and lay them flat in a hot air oven for preheating at 88°C for 8 minutes. Fix the preheated fibers on a stretching device and stretch them to 2.5 times the original length at a constant rate of 10 mm / min. Immediately after the stretching is complete, blow cold air to room temperature to set the shape, and obtain the pretreated polycaprolactone fibers. Seal and store them to avoid moisture.

[0062] Step c: Mix the pretreated cotton fibers and pretreated polycaprolactone fibers in a mass ratio of 10:5 (total weight 700 g) and open them in an opener with a needle spacing of 0.5 mm for 3 times to ensure uniform mixing of the fibers. Send the opened mixed fibers to an air-laid machine and set the working air pressure to 0.6 MPa, the ambient temperature to 25±1°C, and the relative humidity to 60±5% to prepare a web with a grammage of 50±2 g / m 2 Immediately after the web is formed, pre-press it with a pressure roller at 0.5 MPa for 30 seconds to enhance the bonding force between the fibers.

[0063] Step d: Prepare the main network solution: Take 25 g of carboxymethyl chitin (degree of deacetylation 88%) and 15 g of oxidized cellulose nanofilaments (diameter 30 nm) and add them together to 460 mL of deionized water. Stir the mixture at 50°C for 2 hours until it is completely dissolved to form a uniform viscous solution.

[0064] Preparation of auxiliary network dispersion solution: 500 mL of deionized water was added to a beaker, 5 g of hyaluronic acid powder was weighed and added, and a magnetic stirrer was used to stir at a speed of 200 rpm for 30 minutes until the hyaluronic acid was completely dissolved. Then, 1 mol / L sodium hydroxide solution was slowly added dropwise, and the pH of the solution was adjusted to 8.5-9.0 by using pH test paper to detect. 2 g of 1,4-butanediol diglycidyl ether was measured and slowly added to the above solution, while the stirring speed was increased to 300 rpm, and the beaker was placed in a constant temperature water bath at 40°C, and the stirring reaction was continued for 6 hours. After the reaction was completed, the mixture was transferred to a centrifuge tube and centrifuged at a speed of 8000 rpm for 15 minutes, and the supernatant was discarded. The precipitate was washed with deionized water for 3 times, and centrifugal separation was performed after each washing. The washed precipitate was placed in a freeze dryer, pre-frozen at -40°C for 2 hours, and then freeze-dried under a vacuum degree of ≤10 Pa for 12 hours to obtain a hyaluronic acid cross-linking body.

[0065] 20 g of calcium alginate gel microspheres (particle size 30 μm) and 10 g of hyaluronic acid cross-linking body were weighed and added to 300 mL of deionized water, and an ultrasonic device with a frequency of 40 kHz and a power of 300 W was used to treat for 15 minutes until the dispersion was uniform. The web obtained in step c was first immersed in the auxiliary network dispersion solution at a speed of 2 m / min (immersion time 60 seconds), and then the liquid was removed by a 0.2 MPa roller, and then dried in a hot air dryer at 60°C for 2 minutes; then the web was immersed in the main network solution at the same speed (immersion time 30 seconds), and then the liquid was removed by a 0.2 MPa roller, and then dried in a hot air dryer at 60°C for 3 minutes to obtain a water-absorbing web.

[0066] Step e: A nickel template with a height of 30 μm and a pitch of 80 μm hexagonal protrusion array was selected, and the water-absorbing web obtained in step d was laid on the template and placed in a hot press at 70°C and 5 MPa for 5 seconds, then demolded after natural cooling, and a micron-level protruding structure was formed on the surface.

[0067] Preparation of modified nano-silica: 5 g of nano-silica was added to 200 mL of ethanol-water mixed solvent (volume ratio 3:1) and ultrasonically dispersed for 30 minutes; 8 g of γ-glycidoxypropyltrimethoxysilane was added, the pH was adjusted to 4-5 with glacial acetic acid, and the mixture was stirred at 60°C for 4 hours. After centrifugal washing and drying, epoxy nano-silica was obtained. 3 g of dodecyl dimethyl amino propyl ammonium chloride was dissolved in 150 mL of deionized water, and the epoxy nano-silica was added. After stirring at 70°C for 6 hours, centrifugal washing and drying, modified nano-silica was obtained.

[0068] The modified nano-silica was prepared into a 0.5wt% ethanol suspension, and was uniformly sprayed on the surface of the web (the spraying amount was 10% of the mass of the web) by using an electrostatic spraying device (voltage 15kV, flow rate 10mL / min, nozzle distance from the web 15cm). Drying was performed in an oven at 60°C for 10 minutes to obtain the cotton-soft towel base.

[0069] Step f: peach gum polysaccharide 7 parts, collagen 3.5 parts, sodium hyaluronate 2 parts, and glycerol 2 parts were weighed out in parts by weight, added to 85 parts of deionized water, and stirred until completely dissolved to prepare the serum. The serum was uniformly sprayed on the surface of the cotton-soft towel base obtained in step e (the spraying amount was 15% of the mass of the base) by using a spraying device, and then was placed in a vacuum drying oven for drying at 40°C and -0.09MPa for 2 hours. The dried material was cut into pieces by a cutting machine, and was sterilized by irradiation to obtain the degradable cotton-soft towel product.

[0070] Example 4

[0071] A method for preparing a degradable cotton-soft towel, comprising the following steps:

[0072] Step a: 500g of Egyptian long-staple cotton fibers were weighed out and placed in 5000mL of a 5wt% sodium hydroxide aqueous solution, and were stirred at 60°C in a constant-temperature water bath for 20 minutes (stirring rate 200rpm). After the treatment was completed, the fibers were repeatedly rinsed with deionized water until the pH value of the washing liquid reached 7.0±0.2. The alkali-treated cotton fibers were immersed in a cellulase solution prepared with an acetic acid buffer solution having a pH value of 4.8 (enzyme activity 2000U / g, mass / volume ratio of fibers to solution 1:10), and were enzymatically hydrolyzed in a 45°C shaking water bath (150rpm) for 30 minutes. The system was immediately heated to 80°C for 10 minutes to inactivate the enzyme after the enzymatic hydrolysis was completed, and the pretreated cotton fibers were obtained by filtration and were drained in a well-ventilated place for standby use.

[0073] Step b: 200g of polycaprolactone fibers (1.5dtex) were weighed out and were laid flat in a hot air oven for preheating at 90°C for 10 minutes. The preheated fibers were fixed on a stretching device, and were stretched to 3 times the original length at a constant rate of 10mm / min. The stretched fibers were immediately blown with cold air to room temperature for setting, and the pretreated polycaprolactone fibers were obtained and were sealed for storage to avoid moisture absorption.

[0074] Step c: the pretreated cotton fibers and the pretreated polycaprolactone fibers were mixed in a mass ratio of 10:7 (total weight 700g), and were opened in an opener with a needle spacing of 0.5mm for 3 times to ensure uniform mixing of the fibers. The opened mixed fibers were fed into an air-laid machine, and a web having a grammage of 50±2g / m 2The web is then pre-pressed with a 0.5 MPa pressure roller for 30 seconds to enhance the bonding between fibers.

[0075] Step d: Preparation of the primary network solution: 25 g of carboxymethyl chitin (88% deacetylation) and 20 g of oxidized cellulose nanofibril (30 nm in diameter) were weighed and added to 460 mL of deionized water. The mixture was stirred at 50°C for 2 hours until completely dissolved, forming a uniform viscous solution.

[0076] Preparation of the secondary network dispersion solution: 500 mL of deionized water was added to a beaker, and 5 g of hyaluronic acid powder was weighed and added. A magnetic stirrer was used to stir at a speed of 200 rpm for 30 minutes until the hyaluronic acid was completely dissolved. Then, 1 mol / L sodium hydroxide solution was slowly added, and the pH of the solution was adjusted to 8.5-9.0 using pH paper. 2 g of 1,4-butanediol diglycidyl ether was slowly added to the above solution, and the stirring speed was increased to 300 rpm. The beaker was placed in a constant temperature water bath at 40°C, and the stirring was continued for 6 hours. After the reaction was completed, the mixture was transferred to a centrifuge tube and centrifuged at 8000 rpm for 15 minutes. The supernatant was discarded, and the precipitate was washed with deionized water three times. After each washing, the precipitate was centrifuged. The washed precipitate was placed in a freeze dryer and pre-frozen at -40°C for 2 hours, then freeze-dried under a vacuum of ≤10 Pa for 12 hours to obtain a hyaluronic acid cross-linking body.

[0077] Step d: Preparation of the primary network solution: 25 g of carboxymethyl chitin (88% deacetylation) and 20 g of oxidized cellulose nanofibril (30 nm in diameter) were weighed and added to 460 mL of deionized water. The mixture was stirred at 50°C for 2 hours until completely dissolved, forming a uniform viscous solution.

[0078] Step e: A nickel template with a height of 30 μm and a pitch of 80 μm was selected, and the water-absorbing web obtained in step d was placed on the template and placed in a hot press at 70°C and 5 MPa for 5 seconds. After natural cooling, the template was removed, and a micron-level protruding structure was formed on the surface.

[0079] Preparation of modified nano-silica: 5 g of nano-silica was added to 200 mL of ethanol-water mixed solvent (volume ratio 3:1) and ultrasonically dispersed for 30 minutes; 8 g of γ-glycidyloxypropyltrimethoxysilane was added, and the pH was adjusted to 4-5 with glacial acetic acid, and then stirred and reacted at 60°C for 4 hours. After centrifugal washing and drying, the epoxidized nano-silica was obtained. 3 g of dodecyl dimethyl amino propyl ammonium chloride was dissolved in 150 mL of deionized water, and the epoxidized nano-silica was added. After stirring and reacting at 70°C for 6 hours, the product was washed and dried by centrifugation to obtain the modified nano-silica.

[0080] The modified nano-silica was prepared into a 0.5 wt% ethanol suspension, and was uniformly sprayed onto the surface of the fiber web using an electrostatic spraying device (voltage 15 kV, flow rate 10 mL / min, nozzle distance from the fiber web 15 cm) (the spraying amount was 10% of the mass of the fiber web). After drying in a 60°C oven for 10 minutes, the cotton-soft towel base was obtained.

[0081] Step f: 10 parts of peach gum polysaccharide, 5 parts of collagen, 3 parts of sodium hyaluronate, and 3 parts of glycerol were weighed out in parts by weight, and 90 parts of deionized water was added. After stirring until completely dissolved, the serum was prepared. The serum was uniformly sprayed onto the surface of the cotton-soft towel base obtained in step e by a spraying device (the spraying amount was 15% of the mass of the base), and then placed in a vacuum drying oven for drying at 40°C and -0.09 MPa for 2 hours. The dried material was cut into pieces by a cutting machine, and was sterilized by irradiation to obtain the degradable cotton-soft towel product.

[0082] Example 5

[0083] A method for preparing a degradable cotton-soft towel, comprising the following steps:

[0084] Step a: 500 g of Egyptian long-staple cotton fibers were weighed out and placed in 5000 mL of 2 wt% sodium hydroxide aqueous solution. The mixture was stirred in a 50°C constant-temperature water bath for 10 minutes (stirring rate 200 rpm). After the treatment was completed, the fibers were repeatedly rinsed with deionized water until the pH value of the washing liquid reached 7.0±0.2. The alkali-treated cotton fibers were immersed in a cellulase solution prepared with an acetic acid buffer solution with pH=4.8 (enzyme activity 2000 U / g, mass / volume ratio of fibers to solution 1:10), and were subjected to enzymatic hydrolysis in a 45°C shaking water bath (150 rpm) for 30 minutes. After the enzymatic hydrolysis was completed, the system was immediately heated to 80°C for 10 minutes to inactivate the enzyme. After filtration, the pretreated cotton fibers were obtained and were left to drain in a well-ventilated place for standby use.

[0085] Step b: 200 g polycaprolactone fiber (1.5 dtex) was weighed and laid flat in a hot air oven and preheated at 85°C for 5 minutes. The preheated fiber was fixed on the stretching equipment and stretched to twice the original length at a constant rate of 10 mm / min. After stretching, the fiber was immediately blown to room temperature for setting with cold air. The pretreated polycaprolactone fiber was sealed and stored to avoid moisture.

[0086] Step c: The pretreated cotton fiber and the pretreated polycaprolactone fiber were mixed in a mass ratio of 10:3 (total weight 700 g), and put into an opener with a needle spacing of 0.5 mm and opened 3 times to ensure uniform mixing of the fibers. The opened mixed fibers were fed into an air-laid machine, and a web with a grammage of 50±2 g / m 2 was prepared by setting the working air pressure to 0.6 MPa, the ambient temperature to 25±1°C, and the relative humidity to 60±5%. The web uniformity variation coefficient was controlled to be ≤8%. After webbing, the fibers were pre-pressed with a pressure roller at 0.5 MPa for 30 seconds to enhance the bonding force between the fibers.

[0087] Step d: Preparation of the main network solution: 25 g carboxymethyl chitin (degree of deacetylation 88%) and 10 g oxidized cellulose nanofilament (diameter 30 nm) were weighed and added together into 460 mL deionized water. The mixture was stirred at 50°C for 2 hours until completely dissolved, forming a uniform viscous solution.

[0088] Preparation of the auxiliary network dispersion: 500 mL of deionized water was added to a beaker, and 5 g of hyaluronic acid powder was weighed and added to the beaker. A magnetic stirrer was used to stir at a speed of 200 rpm for 30 minutes until the hyaluronic acid was completely dissolved. Then, 1 mol / L sodium hydroxide solution was slowly added, and the pH of the solution was adjusted to 8.5-9.0 using pH paper. 2 g of 1,4-butanediol diglycidyl ether was slowly added to the above solution, and the stirring speed was increased to 300 rpm. The beaker was placed in a constant temperature water bath at 40°C, and the stirring was continued for 6 hours. After the reaction was completed, the mixture was transferred to a centrifuge tube and centrifuged at a speed of 8000 rpm for 15 minutes. The supernatant was discarded, and the precipitate was washed with deionized water for 3 times. After each washing, the precipitate was centrifuged. The washed precipitate was placed in a freeze dryer and pre-frozen at -40°C for 2 hours, and then freeze-dried under a vacuum degree of ≤10 Pa for 12 hours to obtain the hyaluronic acid cross-linker.

[0089] Take 20 g of calcium alginate gel microspheres (particle size 30 μm) and 8 g of hyaluronic acid crosslinking body, add 300 mL of deionized water, and use a 40 kHz, 300 W ultrasonic device to treat for 15 minutes until uniformly dispersed. The fiber web obtained in step c is first immersed in the auxiliary network dispersion solution at a speed of 2 m / min (immersion time 60 seconds), and then the liquid is removed by a 0.2 MPa roller, and then dried in a 60°C hot air drying machine for 2 minutes; then the fiber web is immersed in the main network solution at the same speed (immersion time 30 seconds), and then the liquid is removed by a 0.2 MPa roller, and then dried in a 60°C hot air drying machine for 3 minutes, to obtain a water-absorbing fiber web.

[0090] Step e: Select a nickel template with a height of 30 μm and a pitch of 80 μm hexagonal protrusion array, and lay the water-absorbing fiber web obtained in step d on the template, and place it in a hot press at 70°C and 5 MPa for 5 seconds, then cool naturally and demold, to form a micron-level protruding structure on the surface.

[0091] Preparation of modified nanosilica: Take 5 g of nanosilica and add it to 200 mL of an ethanol-water mixed solvent (volume ratio 3:1), and ultrasonically disperse for 30 minutes; add 8 g of γ-glycidyloxypropyltrimethoxysilane, adjust the pH to 4-5 with glacial acetic acid, and stir at 60°C for 4 hours to obtain epoxidized nanosilica; take 3 g of dodecyl dimethyl amino propyl ammonium chloride and dissolve it in 150 mL of deionized water, add the epoxidized nanosilica, and stir at 70°C for 6 hours to obtain modified nanosilica.

[0092] Prepare a 0.5 wt% ethanol suspension of the modified nanosilica, and use an electrostatic spraying device (voltage 15 kV, flow rate 10 mL / min, nozzle distance from the fiber web 15 cm) to uniformly spray it onto the surface of the fiber web (spraying amount 10% of the mass of the fiber web), and then dry it in a 60°C oven for 10 minutes to obtain a soft cotton towel base.

[0093] Step f: Take peach gum polysaccharide 5 parts, collagen 2 parts, sodium hyaluronate 1 part, and glycerol 1 part by weight, add 80 parts of deionized water, and stir until completely dissolved to prepare a serum. The serum is uniformly sprayed onto the surface of the soft cotton towel base obtained in step e by a spraying device (spraying amount 15% of the mass of the base), and then placed in a vacuum drying oven at 40°C and -0.09 MPa for 2 hours. The dried material is cut into pieces by a cutting machine, and then sterilized by irradiation to obtain a degradable soft cotton towel product.

[0094] Comparative Example 1

[0095] The difference between Comparative Example 1 and Example 1 is that steps a and b are omitted, i.e. the cotton fibers and polycaprolactone fibers are not pretreated.

[0096] Comparative Example 2

[0097] Comparative Example 2 differs from Example 1 in that step d is omitted, i.e. the web is not subjected to the main network solution and the auxiliary network dispersion.

[0098] Comparative Example 3

[0099] Comparative Example 3 differs from Example 1 in that step e is omitted, i.e. the micro-nano protrusion rough structure is not formed on the surface of the web.

[0100] Comparative Example 4

[0101] Comparative Example 4 differs from Example 1 in that the modified nano-silica in step e is replaced by ordinary nano-silica.

[0102] Performance test:

[0103] 1. Biodegradation rate test: According to GB / T 19277.1-2011 standard, 5 g of cut cotton tissue samples were mixed with 50 g of humus soil, deionized water was added to adjust the moisture content to 60%, and incubated in a 25°C constant temperature incubator for 60 days in the dark. After incubation, the mixture was filtered with a 200 mesh screen, the undegraded residue was collected and dried to constant weight (m0). The biodegradation rate was calculated according to the formula: biodegradation rate (%) = (5-m0) / 5 x 100%, each sample was tested 3 times, and the average value was taken. The test results are shown in Table 1.

[0104] 2. Water absorption rate test: The cotton tissue sample was cut into a 10 cm x 10 cm square sample, and the initial mass (m0) was measured. The sample was placed horizontally under a glass funnel with a diameter of 5 cm, and deionized water was added at a constant speed through the funnel to the surface of the sample (flow rate 5 mL / min). The time (t) when the sample was completely saturated with water and no longer penetrated water was recorded, and the mass of the sample after water absorption (m1) was measured. The water absorption rate was calculated according to the formula: water absorption rate (g / s) = (m1-m0) / t, each sample was tested 3 times, and the average value was taken. The test results are shown in Table 1.

[0105] 3. Maximum water absorption capacity test: The centrifugal method was used for testing, 10 cm x 10 cm initial mass m0 sample was soaked in deionized water for 30 minutes to completely swell, taken out with tweezers and hung for 30 seconds to drain surface water, then placed in a centrifuge tube at a speed of 3000 rpm for 10 minutes, and the mass of the sample after centrifugation (m2) was measured. The maximum water absorption capacity was calculated according to the formula: maximum water absorption capacity (g / g) = (m2-m0) / m0, each sample was tested 3 times, and the average value was taken. The test results are shown in Table 1.

[0106] 4. Water retention test: The sample (mass ml) after water absorption to saturation and centrifugation was placed in an environment with temperature 25℃ and relative humidity 60% for 2 hours, and the mass after placement (m2) was weighed. The water retention was calculated according to the formula: water retention (%) = (m2 / ml) x 100%, each sample was tested 3 times, and the average value was taken. The test results are shown in Table 1.

[0107] 5. Surface contact angle test: using a contact angle measuring instrument, 5 μL of deionized water droplets were placed on the surface of the cotton soft towel, an image was taken after 10 seconds and the contact angle was calculated, 5 times were tested at different positions of the sample, and the average value was taken. The smaller the contact angle, the better the hydrophilicity of the surface. The test results are shown in Table 1.

[0108] Table 1:

[0109]

[0110] Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements to part of the technical features, any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method of making a degradable cotton wipe, characterized by, It comprises the following steps: a) taking Egyptian long-staple cotton fibers as raw materials, first treating them with alkali in a sodium hydroxide aqueous solution, and then repeatedly washing them with deionized water until neutral; then immersing the cotton fibers in a cellulase solution prepared with an acetic acid buffer to perform enzymatic hydrolysis, and after the enzymatic hydrolysis is completed, heating and inactivating, to obtain pretreated cotton fibers; b) taking polycaprolactone fibers as raw materials, preheating them in a hot air oven, then stretching them at a constant stretching rate, and then immediately cooling and setting to obtain pretreated polycaprolactone fibers; c) mixing the pretreated cotton fibers and the pretreated polycaprolactone fibers, opening them with a carding machine, and then forming a web with an air-laid machine; d) first preparing a main network solution obtained by dissolving carboxymethyl chitin and oxidized cellulose nanofilament in deionized water; then preparing an auxiliary network dispersion liquid obtained by dispersing calcium alginate gel microspheres and hyaluronic acid crosslinking bodies in deionized water and ultrasonic treatment; immersing the web obtained in step c) in the auxiliary network solution, then removing the liquid with a roller and drying, and then immersing it in the main network solution, removing the liquid with a roller and drying, to build a superabsorbent network inside the web, and obtain an absorbent web; e) adding nanosilica into a mixed solvent of ethanol and water, ultrasonic oscillation and dispersion, then adding γ-glycidyl ether propyltrimethoxysilane, adjusting the pH to 4-5, heating and stirring to react, centrifugal separation, washing and drying to obtain epoxidized nanosilica; adding dodecyl dimethyl amino propyl ammonium chloride into deionized water, stirring and dissolving, then adding epoxidized nanosilica, heating and stirring to react, centrifugal separation, washing and drying to obtain modified nanosilica; selecting a nickel template with a hexagonal array of protrusions, pressing the web in a hot press, then naturally cooling and demolding, forming a micron-level protruding structure on the surface, then preparing an ethanol suspension of modified nanosilica, uniformly spraying it on the surface of the absorbent web with an electrostatic spraying device, and then drying to obtain a cotton-soft towel base; f) spraying the essence liquid on the cotton-soft towel base, then vacuum drying, and finally cutting and irradiation sterilization to obtain the product.

2. A process for the preparation of degradable cotton wipes as claimed in claim 1, wherein, In step a), the concentration of the sodium hydroxide solution is 2-5 wt%, the alkali treatment temperature is 50-60℃, and the alkali treatment time is 10-20 min.

3. The method for preparing a biodegradable cotton towel according to claim 1, characterized in that, In step b), the preheating temperature of the polycaprolactone fibers is 85-90℃, the preheating time is 5-10 min, and the stretching multiple is 2-3 times.

4. A process for the preparation of degradable cotton wipes as claimed in claim 1, wherein, In step c), the mass ratio of pretreated cotton fibers to pretreated polycaprolactone fibers is 10:3-7.

5. The method for preparing a biodegradable cotton towel according to claim 1, characterized in that, In step d), the mass ratio of carboxymethyl chitin to oxidized cellulose nanofilament is 5:2-4.

6. The method for preparing a biodegradable cotton towel according to claim 1, characterized in that, In step d), the mass ratio of calcium alginate gel microspheres to hyaluronic acid crosslinking bodies is 10:4-6.

7. The method for preparing a biodegradable cotton towel according to claim 6, characterized in that, The preparation method of the hyaluronic acid crosslinking body comprises the following steps: adding hyaluronic acid powder into deionized water, stirring and dissolving, then adding sodium hydroxide solution to adjust the pH to 8.5-9.0, then adding 1,4-butanediol diglycidyl ether, heating and stirring to react, washing and freeze-drying to obtain the hyaluronic acid crosslinking body.

8. The method for preparing a biodegradable cotton towel according to claim 1, characterized in that, The step f) comprises the following components by weight: 5-10 parts of peach gum polysaccharide, 2-5 parts of collagen, 1-3 parts of sodium hyaluronate, 1-3 parts of glycerol, 80-90 parts of deionized water.

9. A degradable cotton wipe, characterized in that, Prepared by the method of any one of claims 1-8.

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